Wow - those look excellent. My friends frequently host dumpling night at their house. The wrappers that they use are simply flour and water. As for filling, pork and beef mixed, with cabbage, mushrooms, carrots, lots o' ginger, sesame oil, soy sauce... the veggie ones are the same minus meat. I don't know if they freeze well because we usually eat them all.
Yours look so good- you'll have to let us know what they are like on the repeat
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